The Piechiatrist says: A blast of heat can come in handy

Blueberry-Nectarine Lattice Pie; get the link for the recipe, below. (Deb Lindsey /For The Washington Post)

CORRECTION: An earlier version of the article misstated the temperature at which McDermott first bakes her pies; it is 425 degrees, not 475.

Kate McDermott, the Piechiatrist, once spent 2 1 / 2 years testing just crust recipes and owns 98 pie pans. She conducts workshops in her Port Angeles, Wash., home, which she has dubbed “Pie Cottage,” and holds frequent therapy sessions on Facebook Live. So, who better to turn to for piemaking advice — especially after pulling a somewhat soupy, seasonal-fruit mess from the oven?

Ever positive, the master says she prefers to think of such technical glitches as “challenges” rather than mistakes. Challenge accepted. We caught up with McDermott by phone last week; edited excerpts follow.

Although nothing is yet scheduled, McDermott assures us she will make her way eastward for one of her Art of the Pie workshops.

Kate McDermott far left, in an Art of the Pie workshop held at a Bethesda home in 2012. With her are participants Barbara Kahl, Susie Merriam and Ann Sun (at far right). (Bill O'Leary/Washington Post)

Q: What is the most common mistake people make when baking pies?

A: They overwork their dough. And in doing that, the fats melt. [More on that below.] Also, pay attention to that little voice in you that says, “I think I need to go look at the pie now,” because that may be the time when the pie is going to boil over and you’re going to save it.

Q: What are your key techniques for making crust?

A: Especially in hot weather, it’s important to keep everything chilled. Keep your flour chilled, keep the mixing bowl chilled; remember that butter starts melting at 59 degrees. If the fat is melting, stop and put the mixture back in the freezer or refrigerator. You never want the fats to get too hot while you’re making the dough. And chill the filled pie before you put it in the oven.

Q: What is your favorite dough?

A: My favorite uses a combination of leaf lard and butter. But there are a lot of good pie dough recipes out there. Use the one that works for you.

Q: How do you avoid the dreaded soggy bottom?

A: Put a baking sheet or cookie sheet — some people even use a pizza stone — in the oven as it preheats, and place the filled pie directly on it. You want to give the well-chilled dough a blast of heat for at least 20 minutes to set the bottom crust. If you put it in at a moderate temperature, the crust will just feel like it’s at the beach and start to relax and melt. My general rule is to bake for 20 minutes at 425 degrees and then 40 minutes at 375.

Q: Do you favor a particular type of pie pan over another?

A:I have 98 pie pans. I use them all. I think the standard old glass ones are just fine — plus you can see if your pie is done on the bottom.

I love all the French [ceramic] dishes: Le Creuset, Staub, Emile Henry. They tend to bake evenly and retain heat well. If you’re using a metal pan, make sure it’s not a bright, shiny one, because shiny deflects heat. If you’re using a disposable [aluminium] one, place it inside a glass pan so it has a sturdy surface and also better heat distribution.

Q: How do you make sure your filling is set? What do you do if a fruit pie isn’t bubbling at the end of baking?

A: Make sure you see steady bubbling coming through the vents. If it’s not bubbling, cut an “X” in the center of a large sheet of foil and put the foil over the pie, shiny side down; remember, the shiny side deflects heat. Crank the oven up to 450 for five or six minutes, to blast it with heat. It’s now or never.